Planting Healthy Air: How Trees Can Make Cities More Livable

In this talk Rob will review the results of a global study that reviews the literature on vegetation and human health, and maps the potential for trees to help more than 200 major cities globally. Urban vegetation already plays a small but important role in reducing particulate matter concentrations and ambient air temperatures, but the majority of cities globally are losing vegetative cover over time, so the ability of nature to ensure healthy air is declining over time precisely when billions more people are moving to cities. Looking at city-level averages, however, obscures the power of nature. Nature will not be the solution for air pollution or climate change, but it can serve as a secondary screen to protect vulnerable populations, with measurable health benefits. Rob documents how targeted tree planting can be a cost-effective strategy for ensuring public health in particular locations, while discussing the characteristics of ideal locations for tree planting. He estimates that for the global cities we studied, trees and other vegetation could provide meaningful health benefits to millions of people.